Selected Quarterly Financial Data Unaudited - Selected Quarterly Financial Data (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Apr. 25, 2014	Jan. 24, 2014	Oct. 25, 2013	Jul. 26, 2013	Apr. 26, 2013	Jan. 25, 2013	Oct. 26, 2012	Jul. 27, 2012	Apr. 25, 2014	Apr. 26, 2013	Apr. 27, 2012
Quarterly Financial Data [Abstract]
Net revenues	$ 1,649.0	$ 1,610.0	$ 1,549.9	$ 1,516.2	$ 1,716.5	$ 1,630.1	$ 1,541.2	$ 1,444.6	$ 6,325.1	$ 6,332.4	$ 6,233.2
Total cost of revenues	607.0	607.7	584.7	606.6	684.3	665.2	627.3	594.5	2,406.0	2,571.3	2,519.8
Gross profit	1,042.0	1,002.3	965.2	909.6	1,032.2	964.9	913.9	850.1	3,919.1	3,761.1	3,713.4
Income before income taxes	226.6	229.6	192.2	92.3	188.9	175.8	127.7	74.2	740.7	566.6	712.4
Provision for income taxes	29.6	37.5	25.4	10.7	15.1	17.7	18.1	10.4	103.2	61.3	107.0
Net income	$ 197.0	$ 192.1	$ 166.8	$ 81.6	$ 173.8	$ 158.1	$ 109.6	$ 63.8	$ 637.5	$ 505.3	$ 605.4
Net income per share, basic	$ 0.60	$ 0.57	$ 0.49	$ 0.23	$ 0.48	$ 0.44	$ 0.30	$ 0.17	$ 1.87	$ 1.40	$ 1.66
Net income per share, diluted	$ 0.59	$ 0.55	$ 0.48	$ 0.23	$ 0.47	$ 0.43	$ 0.30	$ 0.17	$ 1.83	$ 1.37	$ 1.58